1. Blue Tooth Communication ROBOTICS – ll MODULE 4

2. Set up a Bluetooth connection between two NXTs. Send/receive messages wirelessly using send/receive message blocks Use one NXT robot as a remote control for another robot Objectives

3. Bluetooth is a wireless technology commonly used in cell phones, headsets, PDAs, laptops, and other portable devices to exchange information without the use of cables. Although its range is limited, it offers a means to communicate with devices using only a small amount of power. Introduction

4. 1. Download an NXT-G program without the USB cable (wirelessly). 2. Exchange information between two robots such as soccer players. 3. Design a remote control to control a moving vehicle wirelessly In this module, you will learn how to send/ receive data wirelessly using send /receive message blocks. Bluetooth communication in NXT- G programs can be used to:

5. Send Message Block

6. The send message block allows you to send a wireless message to another NXT. Send message block can be found in the Action group on the Complete Palette Send Message Block

7. The send message block can be configured using either the configuration panel or using data wires Send Message Block

8. To use the send message block, you set the following parameters: 1.Connection 2.Message 3.Mailbox Send Message Block Connection Message Mailbox

9. * Connection section is used to identify the connection number of the target NXT (the NXT that will receive the message). * It is a value between 0 and 3. Connection

10. The message section includes the message type and the message content. Message The message type (logic, number or text) can be selected from the drop-down menu. Then, you can write your message in the text box immediately below the drop-down menu.

11. Each NXT brick has 10 mailbox numbers where wireless messages can be deposited or stored. Each mailbox number can hold up to five messages. If the mailbox number fills up with five messages, adding one more message will cause the NXT to erase the oldest message. For Example, if a send message block attempts to put a sixth value in Mailbox 5, the first value inserted into Mailbox 5 will be deleted. Mailbox

12. Receive Message Block

13. The receive message block allows you to receive a wireless message from another NXT. Receive message block can be found in the Sensor group on the Complete Palette Receive Message Block

14. The receive message block can be configured using either the configuration panel or using data wires. Receive Message Block

15. To use the receive message block, you set the following parameters: 1.M 2.Compare to 3.Mailbox Receive Message Block Message Compare to Mailbox

16. The message section allows you to select the type of message being received (logic, number or text). Message

17. If you want to compare the incoming message with a text message, either type the test text or number or use the radio buttons to choose the logic test value (True or False). If the test message and the received message are the same, the Yes/No data wire will return a value of “1”; otherwise, it will return a value of “0”. Compare to

18. The mailbox identifies the receiver’s mailbox where the sent message will be stored. Mailbox

19. Lab Activities 1 & 2 + Review Exercises